Skip to content

Commit

Permalink
platform/chrome: Create sysfs attributes for the ChromeOS EC
Browse files Browse the repository at this point in the history 
This adds the first few sysfs attributes for the Chrome OS EC. These
controls are made available under /sys/devices/virtual/chromeos/cros_ec

    flashinfo   - display current flash info
    reboot      - tell the EC to reboot in various ways
    version     - information about the EC software and hardware

Future changes will build on this to add additional controls.

From a root shell, you should be able to do things like this:

    cd /sys/devices/virtual/chromeos/cros_ec
    cat flashinfo
    cat version
    echo rw > reboot
    cat version
    echo ro > reboot
    cat version
    echo rw > reboot
    cat version
    echo cold > reboot

That last command will reboot the AP too.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
  • Loading branch information
@wfrichar @olofj
wfrichar authored and olofj committed Feb 26, 2015
1 parent 8a4be85 commit 71af4b5
Show file tree
Hide file tree
Showing 4 changed files with 280 additions and 1 deletion.
3 changes: 2 additions & 1 deletion drivers/platform/chrome/Makefile
View file
Original file line number Diff line number Diff line change
@@ -1,5 +1,6 @@

obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o
obj-$(CONFIG_CHROMEOS_PSTORE) += chromeos_pstore.o
obj-$(CONFIG_CROS_EC_CHARDEV) += cros_ec_dev.o
cros_ec_devs-objs := cros_ec_dev.o cros_ec_sysfs.o
obj-$(CONFIG_CROS_EC_CHARDEV) += cros_ec_devs.o
obj-$(CONFIG_CROS_EC_LPC) += cros_ec_lpc.o
4 changes: 4 additions & 0 deletions drivers/platform/chrome/cros_ec_dev.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -198,13 +198,17 @@ static int ec_device_probe(struct platform_device *pdev)
return retval;
}

/* Initialize extra interfaces */
ec_dev_sysfs_init(ec);

return 0;
}

static int ec_device_remove(struct platform_device *pdev)
{
struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);

ec_dev_sysfs_remove(ec);
device_destroy(cros_class, MKDEV(ec_major, 0));
cdev_del(&ec->cdev);
return 0;
Expand Down
3 changes: 3 additions & 0 deletions drivers/platform/chrome/cros_ec_dev.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -44,4 +44,7 @@ struct cros_ec_readmem {
#define CROS_EC_DEV_IOCXCMD _IOWR(CROS_EC_DEV_IOC, 0, struct cros_ec_command)
#define CROS_EC_DEV_IOCRDMEM _IOWR(CROS_EC_DEV_IOC, 1, struct cros_ec_readmem)

void ec_dev_sysfs_init(struct cros_ec_device *);
void ec_dev_sysfs_remove(struct cros_ec_device *);

#endif /* _CROS_EC_DEV_H_ */
271 changes: 271 additions & 0 deletions drivers/platform/chrome/cros_ec_sysfs.c
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,271 @@
/*
* cros_ec_sysfs - expose the Chrome OS EC through sysfs
*
* Copyright (C) 2014 Google, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/

#define pr_fmt(fmt) "cros_ec_sysfs: " fmt

#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/kobject.h>
#include <linux/mfd/cros_ec.h>
#include <linux/mfd/cros_ec_commands.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/printk.h>
#include <linux/stat.h>
#include <linux/types.h>
#include <linux/uaccess.h>

#include "cros_ec_dev.h"

/* Accessor functions */

static ssize_t show_ec_reboot(struct device *dev,
struct device_attribute *attr, char *buf)
{
int count = 0;

count += scnprintf(buf + count, PAGE_SIZE - count,
"ro|rw|cancel|cold|disable-jump|hibernate");
count += scnprintf(buf + count, PAGE_SIZE - count,
" [at-shutdown]\n");
return count;
}

static ssize_t store_ec_reboot(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
static const struct {
const char * const str;
uint8_t cmd;
uint8_t flags;
} words[] = {
{"cancel", EC_REBOOT_CANCEL, 0},
{"ro", EC_REBOOT_JUMP_RO, 0},
{"rw", EC_REBOOT_JUMP_RW, 0},
{"cold", EC_REBOOT_COLD, 0},
{"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
{"hibernate", EC_REBOOT_HIBERNATE, 0},
{"at-shutdown", -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
};
struct cros_ec_command msg = { 0 };
struct ec_params_reboot_ec *param =
(struct ec_params_reboot_ec *)msg.outdata;
int got_cmd = 0, offset = 0;
int i;
int ret;
struct cros_ec_device *ec = dev_get_drvdata(dev);

param->flags = 0;
while (1) {
/* Find word to start scanning */
while (buf[offset] && isspace(buf[offset]))
offset++;
if (!buf[offset])
break;

for (i = 0; i < ARRAY_SIZE(words); i++) {
if (!strncasecmp(words[i].str, buf+offset,
strlen(words[i].str))) {
if (words[i].flags) {
param->flags |= words[i].flags;
} else {
param->cmd = words[i].cmd;
got_cmd = 1;
}
break;
}
}

/* On to the next word, if any */
while (buf[offset] && !isspace(buf[offset]))
offset++;
}

if (!got_cmd)
return -EINVAL;

msg.command = EC_CMD_REBOOT_EC;
msg.outsize = sizeof(param);
ret = cros_ec_cmd_xfer(ec, &msg);
if (ret < 0)
return ret;
if (msg.result != EC_RES_SUCCESS) {
dev_dbg(ec->dev, "EC result %d\n", msg.result);
return -EINVAL;
}

return count;
}

static ssize_t show_ec_version(struct device *dev,
struct device_attribute *attr, char *buf)
{
static const char * const image_names[] = {"unknown", "RO", "RW"};
struct ec_response_get_version *r_ver;
struct ec_response_get_chip_info *r_chip;
struct ec_response_board_version *r_board;
struct cros_ec_command msg = { 0 };
int ret;
int count = 0;
struct cros_ec_device *ec = dev_get_drvdata(dev);

/* Get versions. RW may change. */
msg.command = EC_CMD_GET_VERSION;
msg.insize = sizeof(*r_ver);
ret = cros_ec_cmd_xfer(ec, &msg);
if (ret < 0)
return ret;
if (msg.result != EC_RES_SUCCESS)
return scnprintf(buf, PAGE_SIZE,
"ERROR: EC returned %d\n", msg.result);

r_ver = (struct ec_response_get_version *)msg.indata;
/* Strings should be null-terminated, but let's be sure. */
r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
count += scnprintf(buf + count, PAGE_SIZE - count,
"RO version: %s\n", r_ver->version_string_ro);
count += scnprintf(buf + count, PAGE_SIZE - count,
"RW version: %s\n", r_ver->version_string_rw);
count += scnprintf(buf + count, PAGE_SIZE - count,
"Firmware copy: %s\n",
(r_ver->current_image < ARRAY_SIZE(image_names) ?
image_names[r_ver->current_image] : "?"));

/* Get build info. */
msg.command = EC_CMD_GET_BUILD_INFO;
msg.insize = sizeof(msg.indata);
ret = cros_ec_cmd_xfer(ec, &msg);
if (ret < 0)
count += scnprintf(buf + count, PAGE_SIZE - count,
"Build info: XFER ERROR %d\n", ret);
else if (msg.result != EC_RES_SUCCESS)
count += scnprintf(buf + count, PAGE_SIZE - count,
"Build info: EC error %d\n", msg.result);
else {
msg.indata[sizeof(msg.indata) - 1] = '\0';
count += scnprintf(buf + count, PAGE_SIZE - count,
"Build info: %s\n", msg.indata);
}

/* Get chip info. */
msg.command = EC_CMD_GET_CHIP_INFO;
msg.insize = sizeof(*r_chip);
ret = cros_ec_cmd_xfer(ec, &msg);
if (ret < 0)
count += scnprintf(buf + count, PAGE_SIZE - count,
"Chip info: XFER ERROR %d\n", ret);
else if (msg.result != EC_RES_SUCCESS)
count += scnprintf(buf + count, PAGE_SIZE - count,
"Chip info: EC error %d\n", msg.result);
else {
r_chip = (struct ec_response_get_chip_info *)msg.indata;

r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
r_chip->name[sizeof(r_chip->name) - 1] = '\0';
r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
count += scnprintf(buf + count, PAGE_SIZE - count,
"Chip vendor: %s\n", r_chip->vendor);
count += scnprintf(buf + count, PAGE_SIZE - count,
"Chip name: %s\n", r_chip->name);
count += scnprintf(buf + count, PAGE_SIZE - count,
"Chip revision: %s\n", r_chip->revision);
}

/* Get board version */
msg.command = EC_CMD_GET_BOARD_VERSION;
msg.insize = sizeof(*r_board);
ret = cros_ec_cmd_xfer(ec, &msg);
if (ret < 0)
count += scnprintf(buf + count, PAGE_SIZE - count,
"Board version: XFER ERROR %d\n", ret);
else if (msg.result != EC_RES_SUCCESS)
count += scnprintf(buf + count, PAGE_SIZE - count,
"Board version: EC error %d\n", msg.result);
else {
r_board = (struct ec_response_board_version *)msg.indata;

count += scnprintf(buf + count, PAGE_SIZE - count,
"Board version: %d\n",
r_board->board_version);
}

return count;
}

static ssize_t show_ec_flashinfo(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ec_response_flash_info *resp;
struct cros_ec_command msg = { 0 };
int ret;
struct cros_ec_device *ec = dev_get_drvdata(dev);

/* The flash info shouldn't ever change, but ask each time anyway. */
msg.command = EC_CMD_FLASH_INFO;
msg.insize = sizeof(*resp);
ret = cros_ec_cmd_xfer(ec, &msg);
if (ret < 0)
return ret;
if (msg.result != EC_RES_SUCCESS)
return scnprintf(buf, PAGE_SIZE,
"ERROR: EC returned %d\n", msg.result);

resp = (struct ec_response_flash_info *)msg.indata;

return scnprintf(buf, PAGE_SIZE,
"FlashSize %d\nWriteSize %d\n"
"EraseSize %d\nProtectSize %d\n",
resp->flash_size, resp->write_block_size,
resp->erase_block_size, resp->protect_block_size);
}

/* Module initialization */

static DEVICE_ATTR(reboot, S_IWUSR | S_IRUGO, show_ec_reboot, store_ec_reboot);
static DEVICE_ATTR(version, S_IRUGO, show_ec_version, NULL);
static DEVICE_ATTR(flashinfo, S_IRUGO, show_ec_flashinfo, NULL);

static struct attribute *__ec_attrs[] = {
&dev_attr_reboot.attr,
&dev_attr_version.attr,
&dev_attr_flashinfo.attr,
NULL,
};

static struct attribute_group ec_attr_group = {
.attrs = __ec_attrs,
};

void ec_dev_sysfs_init(struct cros_ec_device *ec)
{
int error;

error = sysfs_create_group(&ec->vdev->kobj, &ec_attr_group);
if (error)
pr_warn("failed to create group: %d\n", error);
}

void ec_dev_sysfs_remove(struct cros_ec_device *ec)
{
sysfs_remove_group(&ec->vdev->kobj, &ec_attr_group);
}

0 comments on commit 71af4b5

Please sign in to comment.